Chuck Norris will never have a heart attack. His heart isn't nearly foolish enough to attack him.
This line has brought me a bit of trouble. According to lore, all of Chuck Norris is invincible. His body can withstand even the most intense of damage. However, this joke seems to suggest that if a part of his body were to turn on him, he would destroy it. This reminds me of the "Immovable Object V. Unstoppable Force". Would Chuck Norris be damaged by his actions, or will he be just fine? Would he function better than before?
Final thoughts: I believe Chuck could remove treacherous parts of his body to better suit his needs. Will is all Chuck Norris needs to continue functioning on this plane.